1. Technical Field
The present invention relates to an image display apparatus and an image display method.
2. Related Art
In recent years, high-performance image display apparatuses such as a large screen television and a projector are widely spread. In these image display apparatuses, improvement of an image quality of a display image is becoming more important. In particular, concerning a projector useful as an image display apparatus that has a high degree of freedom of installation and can easily adjust a size of a display image with a so-called zoom function, there is an increasing demand for further improvement of an image quality because of improvement of an image quality of contents displayed on the projector.
Concerning such a projector, JP-A-61-150487 discloses a projector in which a transmissive matrix liquid crystal display device is used as a light valve. The projector includes plural dichroic mirrors, separates light from a light source into three primary colors of R, G, and B with the plural dichroic mirrors, transmits the lights of the respective colors through the liquid crystal display device, and, then, projects the lights on a screen via a projection lens. When the lights are transmitted through the liquid crystal display device, the transmitted lights of the liquid crystal display device are combined by optical means such as a mirror such that two-dimensional pixel arrangements coincide with each other.
In the projector of this type, for example, the number of pixels of the matrix liquid crystal display device is increased to perform light modulation based on an image signal corresponding to content and display an image. This makes it possible to realize improvement of an image quality of a display image.
However, when the number of pixels of an image displayed by the projector is increased, positional adjustment for each of the pixels by an optical system tends to be more difficult. For example, the projection lens included in the projector has chromatic aberration and a refractive index of the projection lens is different depending on wavelength. Therefore, aberration accuracy of the optical system of the projector is required to be higher than that in the past. However, it is difficult to accurately adjust all display positions of sub-pixels forming one pixel.
Shifts of the display positions of such sub-pixels are negligible when the number of display pixels is small. However, according to an increase in the number of display pixels, the shifts of the display positions of the sub-pixels become conspicuous and cause deterioration in an image quality.